CATENARIA ANGUILLULAE SOROKIN: ITS POPULATION IN RHIZOSPHERE OF SOME CROPS AND EFFECT OF SOME OILSEEDS AGAR MEDIA ON ITS GROWTH AND VIRULENCE
Loading...
Date
2016
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Institute of Agricultural Sciences, Banaras Hindu University, Varanasi
Abstract
Catenaria anguillulae an endoparasitic fungus of nematode is widely distributed in soil. It also parasitize on variety of microbes such as liver fluke, rotifers, tape worm, midge eggs and eggs of insects. It grows as saprophyte on various plant debris and small dead animals. The zoospores of this fungus infect nematodes by colonizing near their natural openings like mouth, excretory pore, vulva and anus. The fungus is known to cause disease of nematodes in epidemic form, which indicates its bio-control potential against plant parasitic nematodes. Ten isolates of C. anguillulae were isolated from soils collected from different field crops/fruit trees/fallow fields, using live juveniles of A. tritici as bait.
All the ten isolates of C. anguillulae were isolated by streaking a single infected J2s of A. tritici colonized by zoospores into each of several Petri-dishes containing 0.3% beef extract medium. The pure colonies of ten isolates of fungus were grown on 0.5% linseed agar medium. The cultures were maintained by regular transfer of each isolates on culture media at weekly interval. The isolates were also maintained on J2s of A. tritici in 2 ml. sterilized water in a 50 mm Petri-dish by regular sub-culturing in fortnightly intervals. The growth of all the ten isolates on linseed oil cake media at 30± 1oC varied and isolate No. 1 was fast growing followed by isolate No.7, 5, 9, 8, 4 and 6. Isolate No. 2 had least growth. Virulence test of the isolates using second stage juveniles of A. tritici varied and the fast growing isolate (Isolate No.1) was found to be the most virulent among the all test isolates. The different oilseed (sunflower and groundnut) media along with calcium, salt, honey and whole egg were tested for their efficacy on the growth of C. anguillulae exhibited significantly higher growth of fungus over control. In addition, Medium No. 2 and 3 consisted of egg shell calcium, salt, honey, and whole egg along with groundnut and sunflower oilseeds, respectively, exhibited thick, compact and whitish growth of the fungus followed by Medium No. 4 that involved calcium, salt and honey along with groundnut and sunflower oilseeds @ 0.75 percent without whole egg. Such media also showed effect on the sporangial morphology of the fungus, as they have calcium which is known for its role in cell wall composition. Virulence test of C. anguillulae fifteen days after its growth on the different oilseeds media revealed that all the whole egg, calcium, salt and honey supplemented oilseedsmedia stimulated virulence of the fungus over control (linseed oil cake agar medium). Hence, such media could be used for maintenance of the virulence of the fungus.Media No. 2, 3, 4 and 8 had thick, compact , whitish growth of the fungus exhibiting show growth can be used for the maintenance of fungus with reduce number of sub-culturing. The studies on population of C. anguillulae in rhizosphere of the different crops based on semiquantification using second stage juveniles of A. tritici revealed that most of the test crops had an increase in population of the fungus. Pumpkin and linseed crops stimulated population of C. anguillulae more than twenty folds. Out of the test crops, chilli, cowpea, berseem, Sugarbeet, carrot, wheat, spinach and garlic showed ten folds increases in population of the fungus. Further, it was noticed that garlic which is a non-host crop for root knot nematode exhibited thirteen folds increase in population of C. anguillulae. Hence, such crops can be fitted into disease management module for integrated management of disease caused by plant parasitic nematodes. Since the work was conducted in earthen pots with homogenized soil, it needs to be carried out in bigger size of plots in field having same type of soil for better understanding and applicability. Work is also required to be carried out with respect to chemical composition of root exudates of the crops and their effect on population of C. anguillulae so that one could find reasons behind stimulation in the population of C. anguillulae.
Description
Keywords
Citation
Patel, D. 2016. Catenaria anguillulae Sorokin: its population in rhizosphere of some crops and effect of some oilseeds agar media on its growth and virulence. M. Sc. (Ag.) Thesis, Department of Mycology and Plant Pathology, Institute of Agricultural Sciences, BHU, Varanasi.